[PATCH 1/6] powerpc: eeh: use lock guard for mutex

From: Shrikanth Hegde
Date: Fri Mar 14 2025 - 01:46:38 EST


use guard(mutex) for scope based resource management of mutex.
This would make the code simpler and easier to maintain.

More details on lock guards can be found at
https://lore.kernel.org/all/20230612093537.614161713@xxxxxxxxxxxxx/T/#u

Signed-off-by: Shrikanth Hegde <sshegde@xxxxxxxxxxxxx>
---
arch/powerpc/kernel/eeh.c | 20 +++++++-------------
1 file changed, 7 insertions(+), 13 deletions(-)

diff --git a/arch/powerpc/kernel/eeh.c b/arch/powerpc/kernel/eeh.c
index 83fe99861eb1..929474c0ec77 100644
--- a/arch/powerpc/kernel/eeh.c
+++ b/arch/powerpc/kernel/eeh.c
@@ -1208,16 +1208,16 @@ int eeh_dev_open(struct pci_dev *pdev)
struct eeh_dev *edev;
int ret = -ENODEV;

- mutex_lock(&eeh_dev_mutex);
+ guard(mutex)(&eeh_dev_mutex);

/* No PCI device ? */
if (!pdev)
- goto out;
+ return ret;

/* No EEH device or PE ? */
edev = pci_dev_to_eeh_dev(pdev);
if (!edev || !edev->pe)
- goto out;
+ return ret;

/*
* The PE might have been put into frozen state, but we
@@ -1227,16 +1227,12 @@ int eeh_dev_open(struct pci_dev *pdev)
*/
ret = eeh_pe_change_owner(edev->pe);
if (ret)
- goto out;
+ return ret;

/* Increase PE's pass through count */
atomic_inc(&edev->pe->pass_dev_cnt);
- mutex_unlock(&eeh_dev_mutex);

return 0;
-out:
- mutex_unlock(&eeh_dev_mutex);
- return ret;
}
EXPORT_SYMBOL_GPL(eeh_dev_open);

@@ -1252,22 +1248,20 @@ void eeh_dev_release(struct pci_dev *pdev)
{
struct eeh_dev *edev;

- mutex_lock(&eeh_dev_mutex);
+ guard(mutex)(&eeh_dev_mutex);

/* No PCI device ? */
if (!pdev)
- goto out;
+ return;

/* No EEH device ? */
edev = pci_dev_to_eeh_dev(pdev);
if (!edev || !edev->pe || !eeh_pe_passed(edev->pe))
- goto out;
+ return;

/* Decrease PE's pass through count */
WARN_ON(atomic_dec_if_positive(&edev->pe->pass_dev_cnt) < 0);
eeh_pe_change_owner(edev->pe);
-out:
- mutex_unlock(&eeh_dev_mutex);
}
EXPORT_SYMBOL(eeh_dev_release);

--
2.39.3